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Scene

open class Scene
kotlin.Any
   ↳ androidx.transition.Scene

A scene represents the collection of values that various properties in the View hierarchy will have when the scene is applied. A Scene can be configured to automatically run a Transition when it is applied, which will animate the various property changes that take place during the scene change.

Summary

Public constructors

<init>(@NonNull sceneRoot: ViewGroup)

Constructs a Scene with no information about how values will change when this scene is applied.

<init>(@NonNull sceneRoot: ViewGroup, @NonNull layout: View)

Constructs a Scene which, when entered, will remove any children from the sceneRoot container and add the layout object as a new child of that container.

Public methods

open Unit

Enters this scene, which entails changing all values that are specified by this scene.

open Unit

Exits this scene, if it is the current scene on the scene's scene root.

open static Scene?
getCurrentScene(@NonNull sceneRoot: ViewGroup)

Gets the current Scene set on the given ViewGroup.

open static Scene
getSceneForLayout(@NonNull sceneRoot: ViewGroup, @LayoutRes layoutId: Int, @NonNull context: Context)

Returns a Scene described by the resource file associated with the given layoutId parameter.

open ViewGroup

Gets the root of the scene, which is the root of the view hierarchy affected by changes due to this scene, and which will be animated when this scene is entered.

open Unit
setEnterAction(@Nullable action: Runnable?)

Scenes that are not defined with layout resources or hierarchies, or which need to perform additional steps after those hierarchies are changed to, should set an enter action, and possibly an exit action as well.

open Unit
setExitAction(@Nullable action: Runnable?)

Scenes that are not defined with layout resources or hierarchies, or which need to perform additional steps after those hierarchies are changed to, should set an enter action, and possibly an exit action as well.

Public constructors

<init>

Scene(@NonNull sceneRoot: ViewGroup)

Constructs a Scene with no information about how values will change when this scene is applied. This constructor might be used when a Scene is created with the intention of being dynamically configured, through setting setEnterAction(Runnable) and possibly setExitAction(Runnable).

Parameters
sceneRoot ViewGroup: The root of the hierarchy in which scene changes and transitions will take place.

<init>

Scene(@NonNull sceneRoot: ViewGroup, @NonNull layout: View)

Constructs a Scene which, when entered, will remove any children from the sceneRoot container and add the layout object as a new child of that container.

Parameters
sceneRoot ViewGroup: The root of the hierarchy in which scene changes and transitions will take place.
layout ViewGroup: The view hierarchy of this scene, added as a child of sceneRoot when this scene is entered.

Public methods

enter

open fun enter(): Unit

Enters this scene, which entails changing all values that are specified by this scene. These may be values associated with a layout view group or layout resource file which will now be added to the scene root, or it may be values changed by an setEnterAction(Runnable) enter action}, or a combination of the these. No transition will be run when the scene is entered. To get transition behavior in scene changes, use one of the methods in androidx.transition.TransitionManager instead.

exit

open fun exit(): Unit

Exits this scene, if it is the current scene on the scene's scene root. The current scene is set when entering a scene. Exiting a scene runs the exit action if there is one.

getCurrentScene

@Nullable open static fun getCurrentScene(@NonNull sceneRoot: ViewGroup): Scene?

Gets the current Scene set on the given ViewGroup. A scene is set on a ViewGroup only if that ViewGroup is the scene root.

Parameters
sceneRoot ViewGroup: The ViewGroup on which the current scene will be returned
Return
Scene?: The current Scene set on this ViewGroup. A value of null indicates that no Scene is currently set.

getSceneForLayout

@NonNull open static fun getSceneForLayout(@NonNull sceneRoot: ViewGroup, @LayoutRes layoutId: Int, @NonNull context: Context): Scene

Returns a Scene described by the resource file associated with the given layoutId parameter. If such a Scene has already been created for the given sceneRoot, that same Scene will be returned. This caching of layoutId-based scenes enables sharing of common scenes between those created in code and those referenced by TransitionManager XML resource files.

Parameters
sceneRoot ViewGroup: The root of the hierarchy in which scene changes and transitions will take place.
layoutId ViewGroup: The id of a standard layout resource file.
context ViewGroup: The context used in the process of inflating the layout resource.
Return
Scene: The scene for the given root and layout id

getSceneRoot

@NonNull open fun getSceneRoot(): ViewGroup

Gets the root of the scene, which is the root of the view hierarchy affected by changes due to this scene, and which will be animated when this scene is entered.

Return
ViewGroup: The root of the view hierarchy affected by this scene.

setEnterAction

open fun setEnterAction(@Nullable action: Runnable?): Unit

Scenes that are not defined with layout resources or hierarchies, or which need to perform additional steps after those hierarchies are changed to, should set an enter action, and possibly an exit action as well. An enter action will cause Scene to call back into application code to do anything else the application needs after transitions have captured pre-change values and after any other scene changes have been applied, such as the layout (if any) being added to the view hierarchy. After this method is called, Transitions will be played.

Parameters
action Runnable?: The runnable whose run() method will be called when this scene is entered

setExitAction

open fun setExitAction(@Nullable action: Runnable?): Unit

Scenes that are not defined with layout resources or hierarchies, or which need to perform additional steps after those hierarchies are changed to, should set an enter action, and possibly an exit action as well. An exit action will cause Scene to call back into application code to do anything the application needs to do after applicable transitions have captured pre-change values, but before any other scene changes have been applied, such as the new layout (if any) being added to the view hierarchy. After this method is called, the next scene will be entered, including a call to setEnterAction(Runnable) if an enter action is set.